Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@cassandra.apache.org
Received-SPF: pass (nike.apache.org: domain of zjffdu@gmail.com designates
 209.85.160.44 as permitted sender)
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:in-reply-to:references:date:message-id:subject:from:to
         :content-type:content-transfer-encoding;
        b=aIcDVfTjGsr8DAA0npz9NOnTdxBTjmMlYcB7hzkl4/iV9Uur7QQbrAJLVnhgbDho5T
         xSqaRHv6YLK9eisPBsJfYjNt2MfeN65msSTbaZloXY3BiBbiAiRx7tqn+iawLICPPXeE
         TEDM/NXyvlDSKlfOnqX2bwuE28joT5xIpMtms=
MIME-Version: 1.0
In-Reply-To: <k2qff1a07b81004260312j1201084ej68265f4a6d00dc34@mail.gmail.com>
References: <201004260850245660216@gmail.com>
	 <p2o759d8ad1004251757l37afea7crbbd98fe4e214ad21@mail.gmail.com>
	 <k2qff1a07b81004260312j1201084ej68265f4a6d00dc34@mail.gmail.com>
Date: Wed, 28 Apr 2010 13:49:28 +0800
Message-ID: <h2g8211a1321004272249v3ee48586vba170aac7d8f85d9@mail.gmail.com>
Subject: Re: how to store file in the cassandra?
From: Jeff Zhang <zjffdu@gmail.com>
To: user@cassandra.apache.org
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

Mark,

Thanks for your suggestion, It's really not a good idea to store one
file in multiple columns in one row. The heap space problem will still
exist. And I take your advice to store it in multiple rows, it works,
I can event store one file with 2G.


On Mon, Apr 26, 2010 at 6:12 PM, Mark Robson <markxr@gmail.com> wrote:
> On 26 April 2010 00:57, Shuge Lee <shuge.lee@gmail.com> wrote:
>>
>> In Python:
>>
>> keyspace.columnfamily[key][column] =3D value
>>
>> files.video[uuid.uuid4()]['name'] =3D 'foo.flv'
>> files.video[uuid.uuid4()]['path'] =3D '/var/files/foo.flv'
>
> Hi.
> Storing the filename in the database will not solve the file storage
> problem. Cassandra is a distributed database, and a file stored locally w=
ill
> not be available on other client nodes.
> If you're using Cassandra at all, that probably implies that you have lot=
s
> of client nodes. A non-redundant NFS server (for example) would not offer
> high availability, so would be inadequate for the OP's situation.
> Storing files *IN* Cassandra is very useful because you can then retrieve
> them from anywhere with high availability.
> However, as others have discussed, they should be split across multiple
> columns, or if very big, multiple rows.
> I prefer to split by row because this scales better to very large files.
> During compaction, as is well noted, Cassandra needs the entire row in
> memory, which will cause a FAIL =C2=A0once you have files more than a few=
 gigs.
> Mark


--=20
Best Regards

Jeff Zhang